Bonik Barta graph Severe heat wave over different districts in the country
continues. The temperatures in Jessore, Chuadanga and Pabna on Saturday were over
42 degree Celsius. Temperatures have crossed 40°C-mark in the capital. Several
people died owing to the severe heat wave in different parts of the country.
The weather will remain like this in next 5-7 days, predict meteorologists. This
lengthy severe heat wave is alarming the public health experts. They are of the
opinion that 40 degree Celsius is bearable for the people in dessert areas
where weather is dry. But, this is not at all bearable in tropical countries
like Bangladesh. If the heat wave continues for a long period of time in humid
weather, different communicable and non-communicable diseases may break out.
Even, temperature over 40 degree Celsius may cause human death.
In the tropical countries, people feel temperatures more intensely
due to humidity. Experts say that in tropical country, humidity, solar
radiation and nature of wind increase the negative effects of temperature. Sweat
secretion is a physiological process that cools a human body in hot weather. In
the dessert weather, people sweat, but due to low humidity their sweat vaporizes
quickly. However, it is totally different in cases of the tropical weather. Humidity
is the highest in countries of South Asia, including Bangladesh, and Southeast
Asia. Due to this, it takes longer for the sweat to evaporate, especially in open
and warm outside environment. The high humidity strongly hinder the
physiological cooling process. The ability to control body temperature diminishes
in accordance with the intensity of the hindrance. Heatstroke happens when the
ability to control temperature is fully diminished. Even, a healthy person can
be a victim of heatstroke. A person can have permanent disability or face death
if heatstroke is not treated promptly. People in South and Southeast Asia tend
to die more from heatstroke than any other region in the world.
Wet Bulb Globe Temperature (WBGT) is a unit to measure heat
stress in a human body, which is equivalent to 39 degree Celsius temperature
under full sunlight and 50 percent humidity. The risk of heat-related diseases
increases in proportion to the surpassing of WBGT by temperature and humidity.
The temperatures in different parts of the country, including
capital Dhaka, have crossed 40 degree Celsius. The humidity is over 50 percent
in most places. According to Bangladesh Meteorological Department, among the
divisional cities, Khulna had the highest humidity of 86 percent in the morning
of Saturday. However, it went down to 48 percent in the evening. Humidity in the morning was 80 percent in
Chittagong and Mymensingh. It fell to 57 percent in Mymensingh, but rose to 84
percent in Chittagong. Humidity-wise, Sylhet was the next with 78 percent in
the morning and 75 percent in the evening followed by Rangpur (73 percent in
morning and 67 percent in evening) and Barisal (70 percent in morning and
evening). Humidity in the capital in the morning and evening was 66 percent and
44 percent respectively. In Rajshahi, humidity was 42 percent both in the
morning and evening.
As asked how long the heat wave would continue, meteorologist
Tariful Newaz Kabir told Bonik Barta, “As things stand now, it may continue for
up to seven days. April is the hottest month. On April 17, last year,
temperatures rose to 43 degree Celsius. Weather can change rapidly this time
prior to rainy season.”
“Temperatures
are rising everywhere in the world. The number of trees is going down in urban
areas, including Dhaka. The number of air-conditioners is on the rise. The
number of trees is declining while carbon emission is going up. As a result,
the intensity of heat has become fiercer,” he added.
According to quite a few researches conducted by World Health
Organisation, heat stress caused by severe heat wave increases public health risks,
including kidney and heart failure, pneumonia, transmission of infectious
diseases and decreased ability to control temperature. Besides, physical
condition of the elders and terminally ill people may deteriorate.
United States government’s Department of Health says that
severe heat wave increases environmental and professional risks. According to
US-based scientific journal Annual Review, health systems suffer the most due
to severe heat wave that results in pregnancy-related complications alongside deterioration
of the condition of the terminally ill patients.
Institute of Public Health Director Professor Dr Nasir Uddin
told Bonik Barta, “As we live in a tropical country, the heat wave affects us
more than others. Long term diseases are on the rise. Children and elderly
people are at greater risk. Due to the prevailing weather, no one is
comfortable which increases complications.”
“No should must go under the sun at this moment. Those who
must go should go covering body and head. Normal water with a pinch of salt
should be drunk. Lemon juice or fruit juice should be drunk. Minimum temperatures
inside homes will have to be ensured. One has to be mindful about the type of
food they are taking,” he said.
